The efficiency of the application of high-emissivity coatings on the furnace walls in steam cracking technology can only be evaluated on the asis of a description of radiative heat transfer distinguishing between the frequency bands. To this end, a non-grey gas radiation model based on he exponential wide band model (EWBM) has been developed and applied in the context of three-dimensional CFD s...

Tall oil fractions obtained from Norwegian spruce pulping were hydrodeoxygenated (HDO) at pilot scale using a commercial NiMo hydrotreating catalyst. Comprehensive two dimensional gas chromatography (GC×GC) showed that HDO of both tall oil fatty acids (TOFA) and distilled tall oil (DTO) produced highly paraffinic hydrocarbon liquids. The hydrotreated fractions also contained fatty acid methyl e...

ZSM-5-containing catalytic additives are widely used in oil refineries to boost light olefin production and improve gasoline octanes in the Fluid Catalytic Cracking (FCC) process. Under the hydrothermal conditions present in the FCC regenerator (typically >700 °C and >8% steam), FCC catalysts and additives are subject to deactivation. Zeolites (e.g., Rare Earth USY in the base catalyst and ZSM-...

Thermal cracking of a heavy liquid hydrocarbon was performed in a laboratory scale tubular reactor. Central Composite Design (CCD), was used as an experimental design method. The design variables were Coil Outlet Temperature (COT), feed flow and rate steam ratio. Maximum yield of ethylene was 30.37 wt% at COT, residence time and steam ratio of 869oC, 0.208 s and 1.22 g/g, respect...

in thermal cracking plants, it is desired to apply an optimal temperature profile along the reactor to minimize the operation cost. in this article a simulator is developed by the use of a mathematical model, which describes the static operation of a naphtha thermal cracking pilot plant. the model is used to predict the steady state profiles of the gas temperature and product yields. using a dy...

thermal cracking of a heavy liquid hydrocarbon was performed in a laboratory scale tubular reactor. central composite design (ccd), was used as an experimental design method. the design variables were coil outlet temperature (cot), feed flow and rate steam ratio. maximum yield of ethylene was 30.37 wt% at cot, residence time and steam ratio of 869oc, 0.208 s and 1.22 g/g, respectively. maximum ...

In this work, our methods for the dynamic risk analysis of large alarm databases [1-3], previously tested on a fluidized catalytic cracking unit (FCCU), are extended and tested using data over three years from a steam-methane reformer (SMR) unit at Air Liquide. This paper also introduces methods of providing online estimates that alert operators to potentially serious safety problems. The estim...

This research thesis validates the potential of tall oil as a renewable feedstock for the production of base-chemicals, especially olefins, as conceived in the thermo-chemical bio-refinery concept. The focus was on the use of hydrotreating and steam cracking technologies with different tall oil feedstocks. Particular advances were accomplished in terms of technology development for high yield o...

Introduction Polysulfides play a critical role in the optimization of many chemical processes. Dimethyl disulfide (DMDS), for example, is used as coke inhibiting additive in steam cracking furnaces and can also be used as photolytic initiator during free radical polymerization.[1, 2] Also tetrasulfides are frequently used in chemistry, mostly as inhibitors during polymerization reactions. Despi...

Ñ Anticoking Coatings for High Temperature Petrochemical Reactors Ñ Coke deposition is a major problem for several refinery and petrochemical processes, among which steam cracking for ethylene production. Decreasing coking rates will reduce decoking frequency and will also decrease heat transfer degradation. For these processes, a means of reducing coking phenomena is the application of anticok...